HayaiLearn Reviews 

Signed up for the free trial. Immediately got charged for the month despite the process saying all over the place that it’s a free trial and that I’d be notified before the free trial ends. Only found out as I was trying to cancel the free trial since it wasn’t for me. Contacted support. Never heard back.

EDIT: confirmed that the labels do exist as described. That said, having 2 tiny labels after a couple full screens blasting "FREE TRIAL" (plus a whole signup and onboarding process just to find out about the paywall) is suspiciously intentional. Props for following up. Leaving the review as a potentially helpful pointer for others.

If you consume a lot of Youtube in Japanese, its okay I guess. Not a scam in any case, just not what most people would need, or expect.

But the features about learning words and grammar are just not there yet. I found them more of an annoyance than help. For example, when practicing a word, it loads a random youtube video where they "say" the word, but more often than not, they don't say it - it is simply a transcription error, and they said something else. This left me feeling "okay I totally forgot this word", when in reality, the transcription was wrong. There is no curated/verified list of transcriptions, and no way to flag an error in the transcription.

The collection of already processed media is messy, and my plan to watch Anime episodes is basically non-existent. The only Anime content is trailers and music videos, NOT actual episodes, even for old animes.

There are no good filters for the content, and that was my main blocker in using this app more often. I would suggest using Hayailearn, only if you have a curated list of Japanese youtubers and manually add their videos for processing in the platform. It is not useful to just browse existing content.

There are some great things about this app. For example, the AI explanations at any time during a video are extremely insightful. I don't think many other apps do this nearly as well. I also like how it shows the conjugations of the verbs when you're reading the translations.
There are some not as good things about the app. For example, the videos that are recommended don't update for me and even if I hide videos as non relevant, they keep populating my feed. It's hard to explore content for reasons similar to this. The quizzes can also take a long time because video needs to load first and sometimes the words you're being tested on are used in a completely different context then what you're trying to learn (more for grammar type words vs straight up nouns or adjectives).
The worst thing for me was that I wasn't sure if I was going to keep subscribing to this app. I somehow got subscribed for a year, but I thought I was monthly because I was paying monthly. I cancelled because I wasn't using it and I'm locked in for the whole year. Why would I be in the annual plan when I specifically chose monthly? I'm not a Discord user, so it's not so easy to get answers.
So in the end, really good app if you're going to use it, but if you're experimenting, you should be careful before committing.